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detergent

(Encyclopedia)detergent dētûrˈjənt, dĭ– [key], substance that aids in the removal of dirt. Detergents act mainly on the oily films that trap dirt particles. The detergent molecules have a hydrocarbon portion...

Wu, Chien-Shiung

(Encyclopedia)Wu, Chien-Shiung chyĕnˈ-shyo͝ongˈ wo͞o [key], 1912–97, Chinese-American physicist. She emigrated to the United States from China in 1936 and received a Ph.D. from the Univ. of California, Berke...

time , sequential arrangement of all events

(Encyclopedia)time, sequential arrangement of all events, or the interval between two events in such a sequence. The concept of time may be discussed on several different levels: physical, psychological, philosophi...

clay

(Encyclopedia)clay, common name for a number of fine-grained, earthy materials that become plastic when wet. Chemically, clays are hydrous aluminum silicates, ordinarily containing impurities, e.g., potassium, sodi...

Cherenkov, Pavel Alekseyevich

(Encyclopedia)Cherenkov, Pavel Alekseyevich päˈvĭl əlyĭksyāˈyəvĭch chərĕngˈkəf [key], 1904–90, Soviet physicist. He shared with the Soviet physicists I. M. Frank and I. Y. Tamm the 1958 Nobel Prize i...

Golgi, Camillo

(Encyclopedia)Golgi, Camillo kämēlˈlō gôlˈjē [key], 1844–1926, Italian physician, noted as a neurologist and histologist. He shared with Ramón y Cajal the 1906 Nobel Prize in Physiology or Medicine for wo...

sandblast

(Encyclopedia)sandblast, stream of sand or other abrasive particles driven by a jet of compressed air or water or by centrifugal force against a surface to clean or abrade it. When centrifugal force is used, the ab...

Felton, William Harrell

(Encyclopedia)Felton, William Harrell, 1823–1909, American political leader, b. Oglethorpe co., Ga. After studying medicine he practiced for awhile, but gave it up for farming in 1847. Ordained a Methodist minist...

monitorial system

(Encyclopedia)monitorial system, method of elementary education devised by British educators Joseph Lancaster and Andrew Bell during the 19th cent. to furnish schooling to the underprivileged even under conditions ...

arithmetic

(Encyclopedia)arithmetic, branch of mathematics commonly considered a separate branch but in actuality a part of algebra. Conventionally the term has been most widely applied to simple teaching of the skills of dea...